Bug #78092 [Opn->Fbk]: Opcache shared lockfile and fcntl()

Edit report at https://bugs.php.net/bug.php?id=78092&edit=1 ID: 78092 Updated by: cmb@php.net Reported by: stefan dot djordjevic at humanity dot com Summary: Opcache shared lockfile and fcntl() -Status: Open +Status: Feedback Type: Bug Package: opcache Operating System: Centos 7.6 PHP Version: Irrelevant -Assigned To: +Assigned To: cmb Block user comment: N Private report: N New Comment: Is this still an issue with any of the actively supported PHP versions[1]? Note that "Irrelevant" is no longer supported. [1] <https://www.php.net/supported-versions.php> Previous Comments: ------------------------------------------------------------------------ [2019-05-31 12:11:15] stefan dot djordjevic at humanity dot com Description: ------------ Hi, We got some strange behaviour which seems related to shared lockfile stored on a default path (/tmp/.ZendSem.04tkPY) Randomly our Apache server with forked workers enter in some strange "loop", which slows them down and brings our load and number of apache workers to max. I mange to strace them and what I see is: cntl(10, F_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 fcntl(10, F_SETLK, {l_type=F_UNLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 fcntl(10, F_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 fcntl(10, F_SETLK, {l_type=F_UNLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 fcntl(10, F_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 fcntl(10, F_SETLK, {l_type=F_UNLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 fcntl(10, F_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 fcntl(10, F_SETLK, {l_type=F_UNLCK, l_whence=SEEK_SET, l_start=0, l_len=1}) = 0 . . At one point in time it just passed this "condition" and execute, finish request. File Descriptor is actually pointing to opcode lock files: ls -l /proc/30174/fd/10 lrwx------ 1 root root 64 May 30 13:35 /proc/30174/fd/10 -> /tmp/.ZendSem.04tkPY (deleted) As this condition happens pretty randomly, it's hard to identify real cause of this, but from what I see is that it entering some kind of loop, or race condition with locking - unlocking pattern. I am trying to figure out how we get to this condition, as there are many "variables" included in our new setup (docker containers etc.) I am wondering if you guys have any clue if this can be triggered by some kind of bug in Zend opcode cache-ing mechanism or similar ? Thanks. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=78092&edit=1